This invention relates to key module assemblies of the type frequently used in electrical keyboards. Such keyboards typically contain an underlying printed circuit board having an electrical circuit, and an array of pressure actuatable switches commonly referred to as keys. The keys may be mounted on a chassis plate which is secured to the printed circuit board. Depressing a selected key typically causes a change in the electrical response of the electrical circuit which, in turn, may cause the indicia on the selected key to be recorded, or the function identified by such indicia to be performed.
In many situations it is highly desirable for certain keys in keyboards of the type described to be capable of being illuminated. In the past this has been accomplished by providing a translucent window in a portion of the illuminatable key, and a lamp, such as a light emitting diode (LED), immediately under the translucent window. The leads from the LED are then passed through the chassis plate to the printed circuit board, where they are soldered to appropriate electrical terminals.
Though lighted key module assemblies of the type described have been successful, they are not without significant drawbacks. For example, it is highly desirable to be able to expeditiously remove the chassis plate from the printed circuit board even after the keyboard has been assembled. Such removal is, of course, significantly hampered if the LED leads are soldered to the printed circuit board. Though some attempts to provide a solderless connection have succeeded, this success has typically been at the expense of increasing the cost or the difficulty of assembly.
Accordingly, it is a primary object of this invention to provide an improved lighted key module assembly, and an improved method for mounting a lamp in such an assembly. It is a further object of the invention to provide an improved lighted key module assembly which can be assembled in a keyboard easily and inexpensively. Still another object of the invention is a keyboard assembly of the type described wherein the chassis plate can be expeditiously removed from the printed circuit board even after the keyboard has been assembled.